The present invention relates to a process for preparing pyrrolidine of the formula I
by reacting 1,4-butanediol (BDO) of the formula II
with ammonia in the presence of hydrogen and a supported, metal-containing catalyst.
Pyrrolidine is used inter alia as an intermediate and/or reagent in the production of fuel additives (U.S. Pat. No. 3,275,554 A; DE 21 25 039 A and DE 36 11 230 A), surfactants, drugs and crop protection compositions, hardeners for epoxy resins, catalysts for polyurethanes, and as an intermediate and/or reagent in the production of quaternary ammonium compounds, plasticizers, corrosion inhibitors, as synthetic resins, ion exchangers, textile auxiliaries, dyes, vulcanization accelerators and emulsifiers.
WO 03/051508 A1 (Huntsman Petrochemical Corp.) relates to processes for the amination of alcohols using specific Cu/Ni/Zr/Sn-containing catalysts which, in a further embodiment, comprise Cr instead of Zr (see page 4, lines 10-16). The catalysts described in this WO application comprise no aluminum oxide and no cobalt.
WO 2008/006750 A1 (BASF AG) relates to certain Pb, Bi, Sn, Sb and/or In-doped, zirconium dioxide-, copper-, nickel- and cobalt-containing catalysts and their use in processes for preparing an amine by reacting a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and ammonia, a primary or secondary amine. Aluminum oxide supports are not taught.
WO 2009/080507 A1 (BASF SE) relates to certain Sn- and Co-doped, zirconium dioxide-, copper- and nickel-containing catalysts and their use in processes for preparing an amine by reacting a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and ammonia, a primary or secondary amine. Aluminum oxide supports are not taught.
WO 2009/080506 A1 (BASF SE) describes certain Pb, Bi, Sn, Mo, Sb and/or P-doped, zirconium dioxide-, nickel- and iron-containing catalysts and their use in processes for preparing an amine by reacting a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and ammonia, a primary or secondary amine. Aluminum oxide supports are not taught. Preferably, the catalysts comprise no Cu and no Co.
WO 2009/080508 A1 (BASF SE) teaches certain Pb, Bi, Sn and/or Sb-doped, zirconium dioxide-, copper-, nickel-, cobalt- and iron-containing catalysts and their use in processes for preparing an amine by reacting a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and ammonia, a primary or secondary amine. Aluminum oxide supports are not taught.
WO 2011/067199 A1 (BASF SE) relates to certain aluminum oxide-, copper-, nickel-, cobalt- and tin-containing catalysts and their use in processes for preparing an amine from a primary or secondary alcohol, aldehyde and/or ketone. The preparation of pyrrolidines from 1,4-diols is mentioned in general on page 22, lines 13-15, and page 24, lines 39-42.
WO 2011/157710 A1 (BASF SE) describes the preparation of certain cyclic tertiary methylamines, where an amino alcohol from the group 1,4-aminobutanol, 1,5-aminopentanol, aminodiglycol (ADG) or aminoethyl-ethanolamine is reacted with methanol at elevated temperature in the presence of a copper-containing heterogeneous catalyst in the liquid phase.
WO 2012/049101 A1 (BASF SE) relates to a process for preparing certain cyclic tertiary amines by reacting an amino alcohol from the group 1,4-aminobutanol, 1,5-aminopentanol, aminodiglycol (ADG) or aminoethyl-ethanolamine with a certain primary or secondary alcohol at elevated temperature in the presence of a copper-containing heterogeneous catalyst in the liquid phase.
DE 198 59 776 A1 (BASF AG) relates to certain amination processes using catalyst moldings which comprise oxygen-containing compounds of titanium and of copper and metallic copper.